Minimally Invasive Dentistry and Occlusal Principles

Minimally Invasive Restorative Factors

• Modern adhesive systems
• Advent of restorative materials
• Processing technologies: CAD/CAM
• Implant dentistry
• Conservatism

Prosthetic Options

• Inlays and Onlays
• Resin-bonded bridges
• Zirconia-based single-retainer adhesive FDP

Bonding Protocols

• Deep margin elevation
• Immediate dentin sealing
• Resin coating
• Composite dentin replacement

Advantages of Vertical Preparation

• Minimally invasive in the cervical area
• Saves dental structure and allows enamel preservation
• Flexible finish line positioning based on biologic width
• Ease of impression taking
• Simplified provisional manufacturing and finishing
• Promotes gingival thickening and long-term stability

Components of the Masticatory System

• Structure: Fixed maxillary and movable mandibular components
• Fulcrum: Fixed base and movable complex disk
• Support: Ligaments, encapsulated structures, and muscles
• Neurology: Intricate neurologic controlling system

Synovial Fluid Functions

1. Provides metabolic requirements for nonvascular articular surfaces
2. Acts as a lubricant

Muscles of Mastication

• Masseter
• Temporalis
• Medial Pterygoid
• Lateral Pterygoid (inferior and superior heads)

Factors Determining Tooth Position

• Vertical dimension
• Neutral zone
• Proximal contact
• Occlusal contact

Occlusal Definitions

Centric Relation

Bone-to-bone relation; physiologic centering of the condyles in the cranium. Condyles are in an untranslated, hinge position and can freely rotate on a fixed axis.

Centric Occlusion

Tooth-to-tooth relation where condyles are in centric relation and an untranslated, hinge position.

Maximum Intercuspation

Tooth-to-tooth relation; condyles may or may not be in centric relation. Represents habitual closure or an eccentric position if condyles are out of centricity.

Mandibular Movements

• Opening
• Protrusion and Retrusion
• Lateral Excursions (right and left)

Determinants of Occlusion

• Posterior: TMJ, condylar guidance, mandibular fossa anatomy, and kinematics of the condyles.
• Anterior: Anterior teeth, incisal guidance, labiolingual inclination of maxillary anterior teeth, and overbite/overjet relationship.

Signs of Stable Occlusion

• Uniform bilateral contacts in centric relation
• Absence of posterior interferences during eccentric movements
• Anterior guidance in harmony with the envelope of motion
• No signs of occlusal trauma or instability
• Stable vertical dimension of occlusion